Exchange And Transport Systems: - Mechanisms Of Breathing.

- Mechanisms Of Breathing - 

There is two types of ventilation 

Inspiration = Active process - requires energy 

External intercostal muscle - Contracts 

Internal intercostal muscle - Relax 

Ribs - Upwards and outwards 

Thoracic cavity - Increases in volume 

Diaphragm - Contract 

Expiration = Passive process - does not require 

External intercostal muscle - Relaxes 

Internal intercostal muscle - Contracts

Ribs - Downwards and inwards 

Thoracic cavity - Decreases in volume 

Diaphragm - Relaxes 

Movement of the intercostal muscles = antagonistic - opposing.